Some versions of the present invention generally relate to ultrasonic surgical systems. For instance, some versions relate to an ultrasonic device that allows surgeons to perform cutting, coagulation, and/or fine dissection, such as may be required in fine and delicate surgical procedures such as plastic surgery, etc. It should be understood, however, that the teachings herein may be readily applied to various other types of devices and systems, and need not be limited to the ultrasonic surgical setting.
Ultrasonic surgical instruments may provide substantially simultaneous cutting of tissue and homeostasis by coagulation, which may minimize patient trauma. The cutting action may be realized by an end-effector, or blade tip, at the distal end of the instrument, which transmits ultrasonic energy to tissue brought into contact with the end-effector. Ultrasonic instruments of this nature can be configured for open surgical use, laparoscopic or endoscopic surgical procedures including robotic-assisted procedures, or other types of uses or procedures. Performing a plastic surgery procedure (e.g. abdominoplasty, breast reconstruction/reduction, face lift, etc.) may involve significant recovery time for the patient and risk of post-operative complications such as seroma and hematoma. The recovery time may include additional office visits post-operatively, which may affect patient satisfaction and/or decrease the amount of time a surgeon is available for surgery. In some settings, advanced energy instruments (in lieu of traditional monopolar electrosurgery—“bovie”) may provide a less complicated recovery experience and potentially shorten the post-operative recovery time. However, conventional advanced energy instruments may not be suitable for plastic surgery procedures.
Some surgical instruments utilize ultrasonic energy for both precise cutting and controlled coagulation. Ultrasonic energy may cut and coagulate by using lower temperatures than those used by conventional electrosurgery. Vibrating at high frequencies (e.g., 55,500 times per second), the ultrasonic blade may denature protein in the tissue to form a sticky coagulum. Pressure exerted on tissue with the blade surface may collapse blood vessels and allow the coagulum to form a hemostatic seal. The precision of cutting and coagulation may be controlled by the surgeon's technique and adjusting the power level, blade edge, tissue traction and blade pressure, etc. Some conventional ultrasonic surgical devices may utilize a foot pedal to energize the surgical instrument. The surgeon may operate such a foot pedal to activate a generator that provides energy that is transmitted to the cutting blade for cutting and coagulating tissue while the surgeon simultaneously applies pressure to the handle to press the blade against the tissue. In some settings, the surgeon may lose focus on the surgical field while the surgeon searches for the foot pedal. The foot pedal may also get in the way of the surgeon's movement during a procedure and/or contribute to surgeon leg fatigue (e.g., during long procedures). Some uses of an ultrasonic surgical instrument may include the user using the handpiece of the instrument to apply force to tissue with the blade, even if the blade is not being ultrasonically activated (e.g., “blunt dissection”).
Some conventional ultrasonic surgical devices may have finger actuation of the power at discrete locations along the length of the device. This may make it difficult to move the instrument distally and proximally to gain depth or more control. It may also require the use of a thumbwheel and/or release button to adjust the blade angle, rather than by merely rotating the wrist or rotating the entire device as if the device were a pencil. At least some conventional ultrasonic surgical devices may provide no sensory feedback to the user indicating that the end effector is energized other than momentary switch haptics. The sound created by the end effector may be above the range of human hearing and there may be no tactile vibration in the handpiece. Conventional methods of indicating the active state include an audible beep emitted by the generator. Additional, more instantaneous and local indication of activation could be achieved with visible lighting on the handpiece, audible sound feedback emanated from the handpiece, and/or haptic vibration of the handpiece.
Many types of power activation are known for various devices requiring switch control. Capacitive actuation occurs when a sensor recognizes a change in the dielectric constant of its immediate environment. A commercial example of this is the QTOUCH sensor by Atmel Corporation of San Jose, Calif. In some settings, such sensors or switches may present a risk of inadvertent activation. For instance, a capacitive switch may be inadvertently activated by fluid inadvertently spilled on the surface of the capacitive switch; or by placement of a device incorporating the capacitive switch on a surface, such that the surface activates the capacitive switch. It may therefore be desirable in certain circumstances to differentiate between intentional and unintentional activation; and/or to reduce the likelihood of (if not prevent) unintentional activation of a capacitive switch or similar switch.
One form of resistive technology is the strain gauge. The resistive properties of piezoelectric flouropolymers (PVDF) are a function of applied pressure or strain. In other words, the measured resistance is a function of applied pressure. Actuation is triggered when the applied pressure exceeds a threshold. Another form of resistive technology measures the resistance across a plane of pressure sensitive material; or utilizes the scheme developed by Transparent Products, Inc. of Valencia, Calif. A combination of resistive and capacitive sensing can be used to enhance the sensitivity and tactile feedback while reducing inadvertent activation. A capacitive sensor may require no force, only the presence of the finger to change the dielectric field. A resistive sensor may provide confirmation that a finger (e.g., rather than an accidental fluid) is the source of the dielectric change. Resonant cavity switching technology is offered by ITW ActiveTouch (a division of Illinois Tool Works Inc.) of Buffalo Grove, Ill. Other switching technology may include infrared response to the tip of the human finger to actuate. Still other switching technology may use a resonant, standing wave on a surface that is perturbed by the presence of a finger.
While a variety of ultrasonic surgical instruments have been made and used, it is believed that no one prior to the inventor(s) has made or used an invention as described herein.
The drawings are not intended to be limiting in any way, and it is contemplated that various embodiments of the invention may be carried out in a variety of other ways, including those not necessarily depicted in the drawings. The accompanying drawings incorporated in and forming a part of the specification illustrate several aspects of the present invention, and together with the description serve to explain the principles of the invention; it being understood, however, that this invention is not limited to the precise arrangements shown.